The housings of X-ray tubes used in medical instruments, such as CT scanners, and other analyzers, such as transmission electron microscopes, to which high voltage is applied between the cathode and the anode, and the wall members and high-voltage introduction terminals of large-scale accelerators are required to have high insulation properties. These parts are made of various types of ceramics.
For example, PTL 1 suggests a use of alumina ceramics as the insulating member of a high-voltage bushing of an X-ray tube.